3/8" 24tpi Antenna Connectors

If you like making antennas, especially portable vertical ones, it won't be long before you find a need to grab some (UNF) 3/8" 24 tpi stud connectors.

I really struggled to find a supplier in the UK.  So, if you're in the same position, have a look at:

http://www.a2stainless.co.uk/3-8-UNF-Studding-Connector-Nut_AZEE5.aspx

UK supplier found!

JTDX - An instant success!

Thanks to Bas, PE4BAS, I learned recently about JTDX, a derivative of the popular WSJT-X software.

I'm always interested in any new digital packages, but also always wary of having to spend hours looking at screens as the inevitable software conflicts, PTT/RTS/DTR options and the rest of those things make technology waste one's time.

Luckily, JTDX is much the same in terms of set-up as WSJT-X, so the settings are identical.  It worked straight out of the box, as it were.

Bas said that JTDX is a big improvement on WSJT-X, mainly because it decodes so much more than the original software.

I can testify that Bas's assertion is absolutely correct!  One is faced with 25 or more stations upon decode, and even having several stations responding to my 'CQ' being decoded quickly.  That is very rare for WSJT-X, but common on JTDX.

I did wonder whether, though capable of decoding so much more, many of those stations might be too weak to contact in practice.  This doesn't seem to be the case.  Looking early this morning at JTDX, it's like there's a whole world of stations out there that WSJT-X might not let you realise exists.  I had quite rare stations like Egypt and Peru coming through nicely, although it could have been coincidence.

It's a bit irritating, though, that the waterfall for JTDX seems to cover a wide frequency span, such that the whole thing is too compressed, especially with JT9, for it to be ideal. 

So, like Bas, it's unlikely I'll be reverting to WSJT-X, and look forward to seeing if I can grab a new DX entity out of the noise with JTDX!

Welcome to Amateur Radio! You'll need £5099, though...

This week, my eleven year-old daughter received her much-awaited Foundation Licence certificate from the RSGB.

The certificate is nicely done, and one has then to apply for a callsign via the much-criticised UK regulator, OFCOM.

Sadly for my daughter, and the ham radio contigent in general, OFCOM's online licensing system flatly refused to work properly.  A swift phone call revealed other complaints about the same problem.  A day later, it's still not working.  Big disappointment for anyone, let alone a child.

Alongside the certificate from the RSGB comes a 15-page leaflet - 'Radio Today' (bizarrely, priced at £1.95, even though, like RadCom, it doesn't appear to actually be on sale anywhere) - that aims to help newcomers set up their first station.  It's a dismally dull read, lost the interest of my daughter in seconds (I didn't last much longer), and is full of the usual adverts for wildly expensive equipment.

Indeed, it seems to be mainly driven by adverts, as all magazines are.  The front and back cover feature a rig costing over £5000.  For just an extra £995, you can currently buy a brand new Dacia car!

Why does the RSGB choose this £5100 rig for an introductory text for new hams?  Image: AB4BJ.

The leaflet's 'how to set up' article uses not a second hand unit from e-bay as an example station, but a £1200-odd rig, together with a £250 desk mic and proprietary PSU and speaker.  At least three of those things can be aquired for a fraction of the proprietary vendor's prices, and the rig could be at least half the price for any normal user.  My own boom microphone set-up cost me £11 for the Behringer mike, and £10 for the boom.  Spending £500 more would not make any practical difference.

So, an adverts-driven leaflet that makes ham radio look utterly elitist and unaffordable, especially to those youngsters who haven't a cat's chance in hell of affording an education, house or pension, let alone finding the spare cash for a 'flagship' transceiver.

The RSGB, dominated by ageing middle class, white men, needs to quickly drag itself into the real world of operators flooded by electronics-generated QRM, postage stamp-sized gardens, a regulator that doesn't regulate, and an overwhelming antagonsim towards our hobby.

HF Manpack Success!

I like the convenience of operating from home, where I have a modest, 'kitchen-top' station.

But, using one's home as a radio sation can be intrusive on other members of the family.  It can also be far too much like putting all your eggs in one basket if EMC issues develop in the neighbourhood.

So, I've always kept my hand in simple, rapid deployment of HF radio away from the home, so that, whatever comes to blight me there can be avoided simply by getting in the car and visiting a hill or beach.

My most recent incentive to go portable in earnest came a couple of weeks ago, when a neighbour installed an electric fence right up to my boundary.  Whilst noise blanking gets rid of the ticking almost all the time, and the fence is not that noisy anyway, it does show how easily and quickly neighbour EMC problems can come to influence and possibly spoil your home station.  (Update: three years later, the electric fence was such a maintenance headache that they gave up on it - hurrah!)

So, I took some inspiration from a few images under a Google search for 'HF manpack'. These were all much the same, copper tube constructions that contain all the equipment and are either backpacks in their own right, or otherwise slip into a fabric rucksack.

WSPRlite testing of the copper tube manpack.

I was interested to see whether I could reach any sort of workable match of the tube frame when I mounted a 20m mobile whip on top of it, using a gutter mount, but no ATU.  A quick connection to my SARK-110 antenna analyser showed that, indeed, a perfect and relatively broad match could be achieved quite easily, simply by adjusting the whip length as normal.

Armed with quite a positive first indication from the analyser, I set the frame out in the garden and hooked-up my WSPRlite QRP transmitter, running 200mW.

I left the unit running all day whilst I was out, but conditions were so poor in an R2 blackout that I had no spots at all!  That changed the following day, when conditions relented somewhat, and good distances out to Finland during the day were being achieved.  Later, a few spots out to Russia and the US were reported.

I can tell the bakcpack is working well because, thanks to DXPlorer, the software that comes with WSPRlite, I can compare with known, efficient stations elsewhere in the UK and see that it is as good as, for example, a full wave horizontal loop.  More time is needed for a full assessment.

Clearly, this frame is a workable and efficient solution to not only going mobile but backpack (or pedestrian) mobile, all at very little cost.  Those who operate /PM from the beaches of the UK on a regular basis know how they can manage QRP contacts with VK and ZL very easily, whilst folks at home can't even hear the antipodes!

I'm looking forward to grabbing an FT857 or similar rig, and enjoying morning and evening sessions down the beaches.  Imagine, no noisy solar PV, plasma screens, LCD lights or electric fences anywhere in sight!

UPDATE!

Here are some results from WSPRlite testing.

First, a comparison with a horizontal, large loop antenna:

Next, a comparison with a doublet:

And, finally, against a trapped dipole:

Update 2:

I've now assembled my TS-480 and a 12Ah battery onto the frame.  It's comfortably backpackable, having bought some shoulder straps for it.  The overall experience of using the system on SSB is pretty much identical to operating from a car with a magmount, so I'm pretty happy with that.

The battery is small, but provides enough duration to enable me to cover plenty of overs during the 20-30 minutes of peak long path propagation.  On about 15-20W peak output, I've managed Russia and the mid-west US so far, as well as the usual lot of easy EU stations.  Overall, it is working as well as such a system can be expected to.

An obvious improvement in terms of power duration and ease of transport would be to install the system around a decent, large-wheeled all-terrain pushchair.  Sadly, I sold ours years ago, and that model, which was perfect, is either difficult to find and/or very expensive now.If you go down this route, avoid, at all costs, those buggies with front wheels that swivel, and wheels that are either too narrow, too small, or both!  Wheels needs to be at least 12" in diameter to cope with sand and rough surfaces well.